From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id F064FEE57DF for ; Mon, 11 Sep 2023 09:50:39 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 7B3DF6B0257; Mon, 11 Sep 2023 05:50:39 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 764906B0258; Mon, 11 Sep 2023 05:50:39 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 605256B0259; Mon, 11 Sep 2023 05:50:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 4E5C36B0257 for ; Mon, 11 Sep 2023 05:50:39 -0400 (EDT) Received: from smtpin24.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 2441DC0957 for ; Mon, 11 Sep 2023 09:50:39 +0000 (UTC) X-FDA: 81223846998.24.24D67A1 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf18.hostedemail.com (Postfix) with ESMTP id D68251C0017 for ; Mon, 11 Sep 2023 09:50:36 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=YhXu0nK7; spf=pass (imf18.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1694425836; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=3hI7Q7HmJLGnvJ6TWSuqo/D2NRHYvfG0p6wZ2y0ko6s=; b=UFhY02O33ix6QObuuN9YWh4vN9NQInhyd8jRm1agfLRw9hIy83JUq4Hcujh4LObwijHXe8 dx/T1TZKjLkrtJRoGPTgUHU4bcsH81c1dTCdLDKhgIE71lf5mwuptmHv2fggpuBwFRD5jq aFXhtg0ebJHJbKpbCBotEOMcQI83EuI= ARC-Authentication-Results: i=1; imf18.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b=YhXu0nK7; spf=pass (imf18.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1694425836; a=rsa-sha256; cv=none; b=sE7FBnUTcKgdLSCRBoTvCiOYo3d+deGnDwvxiJ3qvSGhN7v56mJ1UvceAAx003kWLy+gOQ O7QHSQ7XhepfJTR6eIR5G5t9LC+Db5N9YOiCE1ymQ3x97tWo5kPIpF2fonE0CZWpv5QBQG XOvS/wEKiNfF6XO1y0B9MIZcIQYuVZs= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1694425836; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=3hI7Q7HmJLGnvJ6TWSuqo/D2NRHYvfG0p6wZ2y0ko6s=; b=YhXu0nK7mwCQWzxiDBSHYtg/wYz8g1lg0Y/2s8KiClw7tmLXhGjjfnqUNK/DX5jAsAVGOW awea7Jh4vWhSRqOFbWDSr3esL6mQXwsDbWtZ6vhfn7wjrWdavx/331kRQTk+JW0DgQs1Ut Tv0Sl6oXAo1DiMLsuz7ngxuA+yBTjXM= Received: from mail-wm1-f69.google.com (mail-wm1-f69.google.com [209.85.128.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-634-Q7rLanOMOJSsxNE8UDDjBQ-1; Mon, 11 Sep 2023 05:50:35 -0400 X-MC-Unique: Q7rLanOMOJSsxNE8UDDjBQ-1 Received: by mail-wm1-f69.google.com with SMTP id 5b1f17b1804b1-3fe1521678fso30840215e9.1 for ; Mon, 11 Sep 2023 02:50:34 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1694425833; x=1695030633; h=content-transfer-encoding:in-reply-to:organization:from:references :cc:to:content-language:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=3hI7Q7HmJLGnvJ6TWSuqo/D2NRHYvfG0p6wZ2y0ko6s=; b=xCZiqqVY5HP/JuvHhGlIYbSTzDcwZ1AmLaPvrKpY3Pu42XPb6e88YjXCxfRFNzuH6G vxvAXUzEGEQRqUypBYmOyw+P+Z+ErnoFLHXFiim2434guP9t50kbBKlSQuJ/6xRJ+rio tSaMrCX5eozNf/z4xcjcMsgeFPRtdyNVmGEhQobxGoAu68KyQAOFvYVH5XXZTMC27SDs ej2FyTaAHnPXcX4p8KjLVASsgu19+syVsJdoXEL9D+cBPKMpcrO/TntUtA7BJOmQ64kl 2pam3OUCvjaMV5wQdYLZa2TJwQ7yUQTc/ycOawPD00cP3P0fW0KYBGG3zvGbG65SfEW7 tOug== X-Gm-Message-State: AOJu0YwpT2eGCEU5umYwShPx44b2ufqLs3PKgMrftebeEsA75ymo9DQn HcGELEy55o2kg+iFLxDPkyrLvSP6mhNG/IizsP7pJXfTL8ELiWY7UimtodtSOVMLPat/IRNo2W9 ZrNmatqB/6EY= X-Received: by 2002:a05:600c:ad2:b0:3fe:1871:1826 with SMTP id c18-20020a05600c0ad200b003fe18711826mr8233492wmr.27.1694425833710; Mon, 11 Sep 2023 02:50:33 -0700 (PDT) X-Google-Smtp-Source: AGHT+IEj8YJrIUf0UCqWXG8KH6oM4Y88u3/pmtlr2wHp0tLZ2zrPuhEBzJbkMb9F1qoq/xPMcrqORA== X-Received: by 2002:a05:600c:ad2:b0:3fe:1871:1826 with SMTP id c18-20020a05600c0ad200b003fe18711826mr8233473wmr.27.1694425833313; Mon, 11 Sep 2023 02:50:33 -0700 (PDT) Received: from ?IPV6:2003:cb:c743:5500:a9bd:94ab:74e9:782f? (p200300cbc7435500a9bd94ab74e9782f.dip0.t-ipconnect.de. [2003:cb:c743:5500:a9bd:94ab:74e9:782f]) by smtp.gmail.com with ESMTPSA id n8-20020a7bcbc8000000b003fe29f6b61bsm9506299wmi.46.2023.09.11.02.50.32 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 11 Sep 2023 02:50:32 -0700 (PDT) Message-ID: <476456e1-ac50-8e48-260d-5cbe5e8b085e@redhat.com> Date: Mon, 11 Sep 2023 11:50:31 +0200 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.13.0 Subject: Re: [PATCH 1/3] proc/vmcore: Do not map unaccepted memory To: "Kirill A. Shutemov" Cc: Adrian Hunter , Borislav Petkov , Andrew Morton , Dave Hansen , Vlastimil Babka , Mike Rapoport , Lorenzo Stoakes , Tom Lendacky , Baoquan He , Vivek Goyal , Dave Young , linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-coco@lists.linux.dev, linux-efi@vger.kernel.org, kexec@lists.infradead.org References: <20230906073902.4229-1-adrian.hunter@intel.com> <20230906073902.4229-2-adrian.hunter@intel.com> <20230911084148.l6han7jxob42rdvm@box.shutemov.name> <49ab74c8-553b-b3d0-6a72-2d259a2b5bdf@redhat.com> <20230911092712.2ps55mylf7elfqp6@box.shutemov.name> From: David Hildenbrand Organization: Red Hat In-Reply-To: <20230911092712.2ps55mylf7elfqp6@box.shutemov.name> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: D68251C0017 X-Rspam-User: X-Stat-Signature: ca3wcss1cn7ccg8rfucwzs3atf54d9uu X-Rspamd-Server: rspam01 X-HE-Tag: 1694425836-315006 X-HE-Meta: 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 7xBks7Vs 7izMOdyppUtlMcueC3aYyazQPTAYevJXQgrveT0krSFMmgVJza90Z5iT8dp0yMoL4PpcDEISJgEoHchKI77F02hv4ZUS/8Qc9S+9QYkmYXkR6CpL9+PGj5cmtQKP/1FXmF7GMppWrfE3CHqmYkxtbRu6LavfcvdSh8Fhe0qrypj/InRYpaatlMU90wk6WW6vxPnDChgYOa1yqndNfN8TidK3C30Ily0B6xm1ES7CiW5ubQAfzSE4HEQwXbS3ekW+JFmLKb1tMA5rHXTWjnAtglvyTpQSi7SeDeh3EJeuLSPL/wBoaEdAsi+tkReWEBWkIQYH4TU5bYX4tgsQ1m20hHsLHtTyW4oov9z4/uS9KgMR1H3H2UNrmVMAsMh9XfouDMZA2 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On 11.09.23 11:27, Kirill A. Shutemov wrote: > On Mon, Sep 11, 2023 at 10:42:51AM +0200, David Hildenbrand wrote: >> On 11.09.23 10:41, Kirill A. Shutemov wrote: >>> On Mon, Sep 11, 2023 at 10:03:36AM +0200, David Hildenbrand wrote: >>>> On 06.09.23 09:39, Adrian Hunter wrote: >>>>> Support for unaccepted memory was added recently, refer commit >>>>> dcdfdd40fa82 ("mm: Add support for unaccepted memory"), whereby >>>>> a virtual machine may need to accept memory before it can be used. >>>>> >>>>> Do not map unaccepted memory because it can cause the guest to fail. >>>>> >>>>> For /proc/vmcore, which is read-only, this means a read or mmap of >>>>> unaccepted memory will return zeros. >>>> >>>> Does a second (kdump) kernel that exposes /proc/vmcore reliably get access >>>> to the information whether memory of the first kernel is unaccepted (IOW, >>>> not its memory, but the memory of the first kernel it is supposed to expose >>>> via /proc/vmcore)? >>> >>> There are few patches in my queue to few related issue, but generally, >>> yes, the information is available to the target kernel via EFI >>> configuration table. >> >> I assume that table provided by the first kernel, and not read directly from >> HW, correct? > > The table is constructed by the EFI stub in the first kernel based on EFI > memory map. > Okay, should work then once that's done by the first kernel. Maybe include this patch in your series? -- Cheers, David / dhildenb